On April 15, PBS airs "Wonder Women! The Untold Story of American Superheroines" as part of its Independent Lens series. The documentary, which has been making the rounds at film festivals across the country, explores the story of the creation and evolution of Princess Diana of Paradise Island, better known to her fans as Wonder Woman, and the character's legacy of inspiring real-life heroic women.

Filmmaker Kristy Guevara-Flanagan, who also directed the 2008 documentary "Going on 13" and is a former producer for the Independent Lens series, spoke with CBR News about how "Wonder Women!" came into being, the state of women heroes in film, why she believes Wonder Woman has had a difficult time in comics over the past several decades and the reason Diana remains an important figure for audiences today.

CBR News: Wonder Woman's been around for over seven decades. She's had multiple origins, power sets and certainly, costumes. She means different things to different people. What does your film explore?

"Wonder Women!" explores the cultural impact William Moulton Marston's creation has had on society

Kristy Guevara-Flanagan: It follows the career of Wonder Woman from her origin and explores her legacy, characters that probably wouldn't have been created without her. The film also asks, what does it mean when women are heroes in popular culture? We start with comic books -- I think that's a very interesting medium to explore -- and then go to television, since that's where Wonder Woman went.

When did you first become interested in Diana?

I remember Lynda Carter's Wonder Woman on TV when I was growing up, and that was revelatory to me. I wouldn't say I was really a huge fan of superhero comic books, but I saw this article when Gail Simone was hired for the Wonder Woman comic and it mentioned that it was the first time DC [Comics] had hired a woman to be the regular writer and take the helm of the series. I thought that there was some irony there, considering Wonder Woman is this icon of female empowerment.

After that, I dug around and learned about her creator and the original Golden Age stories and I was just immediately taken in. Part of what intrigued me was that the early stories still felt pretty radical, even for our era. Having a female hero at the center of the story, coming from a very matriarchal society, seeing full relationships with other female characters, including her mother. I think now we get a lot more women as superheroes, but usually, it's [part of] an ensemble. You don't get a lot of stories in comic books or film -- TV is a little kinder -- where the woman is really the main hero and not a spin-off from a male version who came first. But here's Wonder Woman. She's the female equivalent of Superman, this is her series and she's the most powerful person in the story. Sometimes just having an adventure/action story with more than one woman in it seems like a surprise.

I was also interested that there were contradictions about her, even in the early stuff, like how her empowerment is coupled with her sexualization. I think that's a tension that's constant in female representation. This was all very interesting to me, and then, when I learned that Wonder Woman was the first person to appear on a cover for "Ms. Magazine," that just sealed the deal. I thought, what a great story to explore, what a great documentary this could be.

Who do you speak to in the documentary?

We talk to a lot of people. We talk to Gloria Steinem, Lynda Carter, Kathleen Hanna, Gail Simone and the Bionic Woman, Lindsay Wagner. There's a little section about how the Riot Girls repurposed images of She-Ra and Wonder Woman. We talk to a lot of people who write about media. Mike Madrid, author of "The Supergirls," is in there. So is Jennifer Stuller, who wrote a really great, fascinating book at women in popular culture, "Ink-Stained Amazons and Cinematic Warriors."

You mentioned Gail Simone's run as the initiating factor in filming the documentary. Does your film delve into the last decade of Wonder Woman or the New 52 version at all?

Fans dressed in costume at the Community Cinema screening in Chicago

The film doesn't go into the last decade in great detail. Unfortunately, with comics nowadays, it seems like within three years, you have a very different origin story and version of the character. It's hard to sum it up. There are certain writer runs that do stand out, of course. Along with Simone, there's George Perez, Phil Jimenez and Greg Rucka. But I don't think Wonder Woman's overall narrative arc has been that strong in the past decade. I'll leave that to hardcore fans to debate.

There definitely seem to be periods where some creators don't seem to know what to do with Wonder Woman, or they make her either a warrior or a princess rather than someone who can be both. We had a year where her history and origin had been altered, leading to a new uniform and personality. Then, just as that story ended, DC Comics rebooted its entire universe, giving us another new costume, personality and origin.

There seem to be regular shifts where they take such a new direction for the character that it becomes like a pinball game rather than a strong narrative. No wonder there hasn't always been as huge a leadership as people might like. It makes the character hard to follow.

Despite all the relaunches she's been through, do you think there's a core to Wonder Woman that still reaches people and comes out strongly when she's most successful?

I think her origin has such a rich history because it involves mythology we're already familiar with. It gives her this loftier place to pull from in terms of material and content. Her Amazonian past and living on an island with all women obviously works; it's always present in her story. I think it's a shame that they've changed that to make her Zeus' daughter, because being someone born the way she was made her very different and cool. I think she works best when she has a global perspective and she's not so quick to use violence, although she will if she has to.

She's on the more warrior side right now. The Amazons of Greek mythology were definitely no nonsense in displaying their strength, so maybe she's more accurate to the old idea of an Amazon, but that's not what her creator William Moulton Marston intended. I think diplomacy and teaching and trying peaceful solutions first was what was intended to be at her core. I also think Wonder Woman works best when she has a sense of humor. She's a noble character, but she has to be able to poke fun at herself.

Like Superman, she's a hard character to update, partly because she was created during a time when superheroes weren't very nuanced. Then again, even though they both could be considered old fashioned, we keep taking chances on new Superman movies and TV shows and cartoons. Batman was created along the same time, and we keep updating him. I think there's great potential for making her a relevant character today. She has a great world view and political overtones. She fights gods and super-villains, but she also fights for truth itself and wants to empower women around the world. That's a different kind of superhero and it's really topical that she often fights for underprivileged people.

Cartoonist and comics historian Trina Robbins with fans at a screening of the documentary at the Spokane International FIlm Festival

Considering her long history and wide recognizability, it seems strange that we don't have a feature film in the works and that the proposed ideas for a television series keep going back to the drawing board. What are your thoughts on that?

Unfortunately, it's still seen as economically risky to put a woman in the lead for an action film and not have it be an ensemble. There have been flops such as "Elektra" and "Catwoman," and the consensus is that young men don't want to see a powerful woman on screen. They seem largely afraid of even trying, but it seems like a no-brainer to just adapt the basic story we know of her, the island and being born out of clay and going out into the world. Why try to totally change that story? I think films like "The Hunger Games" shows that we can have a success with that. Even "Twilight" has a leading female character, though not superpowerful.

There seems to be a trend in action films these days that if a woman is physically formidable, then she's psychologically damaged or unstable. The latest idea for a Wonder Woman TV show has suggested showing her as a younger, less powerful character rather than as an adult superhero, similar to "Smallville." Do you think some people are more willing to take a chance on stories like "Brave" and "The Hunger Games" rather than Wonder Woman because they're more comfortable with physically formidable teenage girl heroes rather than a physically formidable adult woman?

That's a really good point. I think so. I think it's a little more threatening to some people when it's a woman instead of a girl. Plus, I think it's seen as more plausible for a teenager or someone coming of age to explore heroism and idealism rather than an adult doing the same. And having a powerful woman who's also unstable or seriously traumatized by physical abuse or rape seems sometimes a weird need to justify her being a warrior.

I have noticed a pattern of progression and then a backlash to less physically powerful women. When you do have some success like "Buffy the Vampire Slayer," it seems to cause a sea change for a while, but then we resort back. There's a variety of reasons for it. It's hard to point the finger at one thing. I think it also has to do with where we are politically.

Ultimately, what do you want viewers to get out of your film?

I hope audiences -- from the studio executives to the comic writers and artists to the young people just noodling around in their notebooks -- are inspired to create more female heroes and other heroes that truly reflect the world in which we all live. I hope audiences will support women as creators and films and series with women as the leading protagonist by buying tickets and books to see these . Finally, I hope audiences will stand up to demand producers create the kinds of images and stories they want to see, write the kind of plot lines that make them feel strong and empowered.

"Wonder Women! The Untold Story of American Superheroines" debuts April 15 at 10 PM on PBS.